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<a name="Invoking"></a>
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<p>
Next: <a href="Syntax.html#Syntax" accesskey="n" rel="next">Syntax</a>, Previous: <a href="Overview.html#Overview" accesskey="p" rel="prev">Overview</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Command_002dLine-Options"></a>
<h2 class="chapter">2 Command-Line Options</h2>

<a name="index-options_002c-all-versions-of-assembler"></a>
<p>This chapter describes command-line options available in <em>all</em>
versions of the <small>GNU</small> assembler; see <a href="Machine-Dependencies.html#Machine-Dependencies">Machine Dependencies</a>,
for options specific
to particular machine architectures.
</p>

<p>If you are invoking <code>as</code> via the <small>GNU</small> C compiler,
you can use the &lsquo;<samp>-Wa</samp>&rsquo; option to pass arguments through to the assembler.
The assembler arguments must be separated from each other (and the &lsquo;<samp>-Wa</samp>&rsquo;)
by commas.  For example:
</p>
<div class="smallexample">
<pre class="smallexample">gcc -c -g -O -Wa,-alh,-L file.c
</pre></div>

<p>This passes two options to the assembler: &lsquo;<samp>-alh</samp>&rsquo; (emit a listing to
standard output with high-level and assembly source) and &lsquo;<samp>-L</samp>&rsquo; (retain
local symbols in the symbol table).
</p>
<p>Usually you do not need to use this &lsquo;<samp>-Wa</samp>&rsquo; mechanism, since many compiler
command-line options are automatically passed to the assembler by the compiler.
(You can call the <small>GNU</small> compiler driver with the &lsquo;<samp>-v</samp>&rsquo; option to see
precisely what options it passes to each compilation pass, including the
assembler.)
</p>

<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top">&bull; <a href="a.html#a" accesskey="1">a</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-a[cdghlns] enable listings
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="alternate.html#alternate" accesskey="2">alternate</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;alternate enable alternate macro syntax
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="D.html#D" accesskey="3">D</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-D for compatibility
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="f.html#f" accesskey="4">f</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-f to work faster
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="I.html#I" accesskey="5">I</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-I for .include search path
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="K.html#K" accesskey="6">K</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-K for difference tables
</td></tr>
<tr><th colspan="3" align="left" valign="top"><pre class="menu-comment">
</pre></th></tr><tr><td align="left" valign="top">&bull; <a href="L.html#L" accesskey="7">L</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-L to retain local symbols
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="listing.html#listing" accesskey="8">listing</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;listing-XXX to configure listing output
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="M.html#M" accesskey="9">M</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-M or &ndash;mri to assemble in MRI compatibility mode
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="MD.html#MD">MD</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;MD for dependency tracking
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="no_002dpad_002dsections.html#no_002dpad_002dsections">no-pad-sections</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;no-pad-sections to stop section padding
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="o.html#o">o</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-o to name the object file
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="R.html#R">R</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-R to join data and text sections
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="statistics.html#statistics">statistics</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;statistics to see statistics about assembly
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="traditional_002dformat.html#traditional_002dformat">traditional-format</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">&ndash;traditional-format for compatible output
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="v.html#v">v</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-v to announce version
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="W.html#W">W</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-W, &ndash;no-warn, &ndash;warn, &ndash;fatal-warnings to control warnings
</td></tr>
<tr><td align="left" valign="top">&bull; <a href="Z.html#Z">Z</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">-Z to make object file even after errors
</td></tr>
</table>

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